Queuemail plugin is a centralised email queueing system configurable for many providers all centrally controlled and limited to either daily limit or failures exceeding failureTolerance limit (in a row). By default all email's passing through are priority driven and configured by overall customService name. Two methods of priority queueing are provided BASIC and ENHANCED (default). Enhanced launches an additional thread for each running task and will attempt to kill any running process considered as stuck (if time taken exceeds killLongRunningTasks configuration period).